public static ICollection<string> SplitSentence(string sentence)
{
List<string> result=new List<string>();
StringBuilder sb=new StringBuilder();
foreach (char c in sentence)
{
if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')||c=='-')
{
sb.Append(c);
}
else
{
string word = sb.ToString();
if (word != "")
{
result.Add(word);
}
sb.Clear();
result.Add(c.ToString());
}
}
var last = sb.ToString();
if (last != "")
{
result.Add(last);
}
return result;
}